1995 Chevy silverado with a

1995 Chevy silverado with a 5.7. Was running fine i stopped at a stoplight and it died. It was hard starting, i had to turn the AC off to get it to start, then had to 2 feet it home. Now it starts and idles rough, it does the surge thing when in park. When i put it in gear the truck dies, when i turn AC on the truck dies. When i try to drive it, and give it gas the truck runs rough and has no power at all once i get RPMS above 2200 the truck runs just fine. Truck runs great on the high way but dies when i stop. I have changed spark plugs, wires, fuel filter, cleaned injectors and i THINK i got all vacuum lines checked for leaks. what am i missing.